The present invention relates to surgical devices. More specifically, the invention relates to devices for performing transluminal angioplasty utilizing an expandable balloon member mounted on and affixed to a hollow guidewire. The balloon may be inflated by introducing a fluid or a gas through the guidewire and into the expandable balloon member to thereby dilate a lesion within a blood vessel.
Devices for performing transluminal angioplasty are known in the art. Such devices are used in procedures by which obstructions in blood vessels are altered in order to increase blood flow through the obstructed area of the vessel. Typically, a partially occluded blood vessel is enlarged by use of a balloon catheter that is passed percutaneously through the arterial system until the balloon member is properly positioned at the site of the occlusion or lesion. The properly positioned balloon member is then inflated to dilate the lumen of the blood vessel at the site of occlusion. Balloon catheters typically include thin flexible lengths of tubing having a small inflatable balloon mounted at or near the distal end of the tubing. The catheters are designed to be inserted and positioned within the lumen of a blood vessel, typically with fluoroscopic guidance and by use of a guidewire for improving the pushability or trackability of the otherwise flexible tubing.
The utility of prior art angioplasty catheters has typically been limited, in one aspect, by the available dimensions of the synthetic tubing relative to the internal diameter of the vessel requiring treatment. This limitation is especially significant where the catheter includes inner and outer catheter tubes to allow for the sampling and further treatment of the patient's blood during performance of the angioplasty procedure. Further, the need for and the use of a solid metallic guidewire to improve the pushability or trackability of the otherwise flexible synthetic catheter has necessarily required a cross-sectional catheter diameter greater than that of the guidewire. Such dimensional limitations have prevented prior art angioplasty catheters from being used in certain narrow blood vessels.
The present invention provides an apparatus for performing transluminal angioplasty which may be utilized in blood vessels of very small cross-sectional diameter as well as in blood vessels of larger diameter. In its preferred embodiment, the apparatus of the present invention includes a hollow stainless steel guidewire with an expandable balloon member affixed to the hollow guidewire at or near the distal end thereof.
The use of stainless steel, or another suitable metallic material, provides a catheter having an extremely small outer diameter while imparting good torque control and excellent pushability. The stainless steel guidewire is radiopaque to facilitate viewing of the catheter by use of a fluoroscope when the catheter is passed percutaneously through the arterial system. A high degree of torque control allows the stainless steel catheter to be vibrated or even rotated to aid in the insertion of the catheter and in the emulsification of blood clots within the treated blood vessel.
It is accordingly an object of the present invention to provide an apparatus for performing transluminal angioplasty.
It is another object of the present invention to provide an apparatus for performing transluminal angioplasty which utilizes a catheter having an extremely small cross-sectional diameter.
It is still another object of the present invention to provide an apparatus for performing transluminal angioplasty wherein the apparatus includes a catheter which provides good torque control during the insertion of the apparatus within the arterial system.
It is still another object of the present invention to provide an apparatus for performing transluminal angioplasty which has excellent pushability or trackability.